Sadness is a severe pain related to being sorrow, feeling alone and helpless, which results from negative outcomes. . .Sadness can be viewed as a temporary lowering of mood, whereas depression is more chronic.
Depression is a state of low mood. . .Depressed people may feel sad, anxious, empty, hopeless, worried, helpless, worthless, guilty, irritable, hurt, or restless. They may lose interest in activities that once were pleasurable, experience loss of appetite or overeating, have problems concentrating, remembering details, or making decisions, and may contemplate or attempt suicide. Insomnia, excessive sleeping, fatigue, loss of energy, or aches, pains, or digestive problems that are resistant to treatment may also be present.